I-Methyl imidazole

Die Cyclisierung der oc-Guanidino-carbonsauren fiihrt zu2-Amino-4-hydroxy-imidazolen. Nach dieser Methode crhalt man z. B. durch Erhitzen von N -Carboxymethyl-N -methyl-gua-nidin (Kreatin) in Salzsaure in 80% Ausbeute 2-Amino-4-hydroxy-I-methyl-imidazol (Kreati-ninf61 ... 

Durch Erhitzen von 4(5)-Azidocarbonyl-imidazol in tert.-Butanol wird in 41 % Ausbeute 4(5)-tert.-Butyloxycarbonylamino-imidazol erhalten998. Analog fiihrt die Umsetzung von 4(5)-Hydrazinocarbonyl-l-methyl-imidazol mit Natriumnitrit/Salzsaure nach anschlieBender Ther-molyse des so erhaltenen Carbonsaure-azids in tert.-Butanol zu 5-tert.-Butyloxycarbonyl-amino-I-methyl-imidazol (88%)999 ... 

Mt/i methyl imidazoles Cu(l-CH3 C3H3N3) Cl3-2H30 6° ) room 1.84 tetragonal coordination suggested 69G22... 

Methimazole, 2-mercapto-i-methyl-imidazole ( Mercazole ), a useful agent in thyrotoxicosis, is usually given as the 2-ethoxycarbonyl-derivative (i.j6) (carbimazole, Neo-Mercazole ) which forms a depot. 

Gas-phase pK values for azoles are unavailable except for imidazole and 1-methyl-imidazole. Imidazole is ca. 75kJmor more basic than ammonia, i.e. approximately the same as pyridine 1-methylimidazole is about 29kJmor more basic than imidazole (82PC40200). 

Imidazole, I-methyl-dipole moment, 5, 351 (7ICHE80I) kinetic data, 6, 21 (73AJCI949)... 

Bis[Ar,Ar -di(2-pyridyl)- and -di(2-pyridyl-methyl)-imidazol-2-ylidene]aurate(i) tetrafluoroborates have been prepared from the analogous silver complexes on reaction with (tht)AuCl and their structures determined. The configuration of the cations with sterically well-protected two-coordinate gold centers shows no anomalies. However, fascinating structures are found for the adducts with silver tetrafluoroborate obtained as acetonitrile... 

Carboxy-l-methyl-imidazol535 Man erhitzt eine Suspension von 3,4 g (20 mmol) 4,5-Dicarboxy-l -methyl-imidazol in 100 ml Essigsaureanhydrid 4 h auf 100°. Die danach homogene Reaktionsmischung wird i. Vak. zur Trockene eingedampft. Dann wird der Ruckstand mit Aceton gewaschen und aus Ethanol umkristal-lisiert Ausbeute 2,5 g (99%) Schmp. 257° (Zers.),... 

Sehr einfach einzufuhrende und abspaltbare (s. S. 99 f.) Schutzgruppen fiir die 1-Position von Imidazolen sind die Dimethoxy-methyl- und die Diethoxy-methyl-Gruppe. Die 1 -(Dialkoxy-methyl)-imidazole werden durch Erhitzen von Imidazolen mit Orthoameisensaure-tricstern unter Katalyse mit 4-Methyl-benzolsulfonsaure erhalten713 [Vorschrift fiir I-(Diethoxy-methyl)-imidazol s. Bd. E5/1, S. 136]. 

I-(2,6-Dimethyl-phenyl) -2-phenyl-5-( 2,2,2- trifluor-ethoxy ) -4- trifluor-methyl-imidazol 59%... 

Der Austausch des Sauerstoff-Atoms in 1-substituierten Imidazol-3-oxiden durch Nukleophile verlauft unter Angriff des Nukleophils in 2-Position. So erhalt man z. B. aus 1-Benzyl-4,5-dimethyl-imidazol-3-oxid mit Kaliumcyanid/Dimethylsulfat I-Benzyl-2-cyan-4,5-dime thy l-imidazol (65%), mit Phosphoroxychlorid l-Benzyl-2-chlor-4,5-dimethyl-imidazol (72%) bzw. mit Butindisaure-dimethylester l-Benzyl-2- (1,2-dimethoxycarbonyl-2-oxo-ethyl)-4,5-dimethyl-imidazol (83%)962. Analog wird l-Benzyl-5-methyl-imidazol-3-oxid mit z.B. Kaliumcyanid/Dimethylsulfat zu l-Benzyl-2-cyan-5-methyl-imidazol (75%) umgesetzt962. 

Bis[iV,iV -di(2-pyridyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis[iV,iV -di(2-pyridyl-methyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis(diselenolate) complexes, dinuclear iron compounds, 6, 242 Bis(dithiolene) compounds, in tungsten carbonyl and isocyanide complexes, 5, 644 Bis(enolato) complexes, with bis-Cp Ti(IV), 4, 589 Bis(enones), in reductive cyclizations, 10, 502 Bis(ethanethiolato) complexes, with bis-Cp Ti(IV), 4, 601 Bis(ethene)iridium complexes, preparation, 7, 328-329 -Bis(fluorenyl)zirconocene dichlorides, preparation,... 

CA nomenclature (3.S-m)-3-ethyIdihydro-4-[(I -methyl-1 //-imidazol-5-yl)methyl]-2(3//)-furanone. 

Even a rod-like backbone derived from acetylene is conceivable and has been realised by Liu et al. [367] starting from l,4-dichlorobutin-2. The usual reaction with methyl imidazole and subsequent reaction with silver(l) oxide and carbene transfer to gold(I) [Au(SEtj)Cl] makes the dimeric silver(I) and gold(l) complexes accessible featuring argentophilic and aurophilic interactions, respectively. 

Goff, D.A., Koolpe, G.A., Kelson, A.B., Vu, H.M., Taylor, D.L., Bedford, C.D., Musallam, H.A., Koplovitz, I., Harris, R.N. (1991). Quaternary salts of 2-[(hydroxyimino)methyl]imidazole. 4. Effect of various side-chain substituents on therapeutic activity against anticholinesterase intoxication. J. Med. Chem. 34 1363-8. 

The mass spectrum of I-methyl-4-nitroimidazole-5-carboxylic acid amide shows the elimination of water by an electron impact as distinct from the usual thermal process. In l,4,5-trimethylimidazole-2-carboxylic acid the principal loss is that of CO2. Subsequent loss of O, OH, and HCN was also observed (Schofield et al., p. 173). Ferguson and Schofield (pp. 172,173) have reported considerable data for imidazole JV-oxides. Thus 1-methoxy-4,5-dimethyl-2-phenylimidazole (which loses OCH3 and CH3CN from the fragment m/e 171) is readily distinguished from l,4,5-trimethyl-2-phenyl-imidazole 3-oxide (loss of O and OH). The spectra of 1-benzylimidazoles are dominated by the tropylium ion. ... 

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